Hydrothermal synthesis and characterization of metavanadate containing spiral chain: Ni(en)3(VO3)2

The hydrothermal reaction of V2O5, NiCl2·6H2O, ethylenediamine and H2O in the mole ratio 1:1:4.9:120 at 150°C for 55 h produced violet prismatic crystals of Ni(en)3(VO3)2. The crystal of the title compound is hexagonal P61, a=8.986(1), c=34.031(2) Å, V=2379.8(5) Å3, Z=6, Dcalc=1.829 g cm−3 and R=0.0609 for 1406 observed reflections. The structure of Ni(en)3(VO3)2 consists of spiral anion (VO3)∞ chains formed by corner-sharing VO4 tetrahedra with Ni(en)3 2+ complex cations occupying the interchain positions, where there are electrostatic interactions and hydrogen bonds between the anion chain and the complex cation. The title compound is the first example of a vanadium compound, in which the repeat unit of the chain is 12-nuclear corner-sharing tetrahedra, V12O36. The magnetic susceptibility of the title compound has been studied.